217 citations · 1.5k across the 34 of their papers we have counts for
34 papers
Exact and lower bounds for the quantum speed limit in finite dimensional systems
Mattias T. Johnsson, Lauritz van Luijk, Daniel Burgarth
A fundamental problem in quantum engineering is determining the lowest time required to ensure that all possible unitaries can be generated with the tools available, which is one o…
Open loop linear control of quadratic Hamiltonians with applications
Mattias T. Johnsson, Daniel Burgarth
The quantum harmonic oscillator is one of the most fundamental objects in physics. We consider the case where it is extended to an arbitrary number modes and includes all possible…
Probing many-body correlations using quantum-cascade correlation spectroscopy
Lorenzo Scarpelli, Cyril Elouard, Mattias Johnsson +7
The radiative quantum cascade, i.e. the consecutive emission of photons from a ladder of energy levels, is of fundamental importance in quantum optics. For example, the two-photon…
Modified coherence of quantum spins in a damped pure-dephasing model
Mattias T. Johnsson, Ben Q. Baragiola, Thomas Volz +1
We consider a spin- particle coupled to a structured bath of bosonic modes that decay into thermal baths. We obtain an analytic expression for the reduced spin state and use it…
Generating nonlinearities from conditional linear operations, squeezing and measurement for quantum computation and super-Heisenberg sensing
Mattias T. Johnsson, Pablo M. Poggi, Marco A. Rodríguez +2
Large optical nonlinearities can have numerous applications, ranging from the generation of cat-states for optical quantum computation, through to quantum sensing where the sensiti…
Geometric pathway to scalable quantum sensing
Mattias T. Johnsson, Nabomita Roy Mukty, Daniel Burgarth +2
Entangled resources enable quantum sensing that achieves Heisenberg scaling, a quadratic improvement on the standard quantum limit, but preparing large scale entangled states is ch…